physical and chemical changes - 7.6c\n4 an experiment was performed in which a crystalline substance was…

physical and chemical changes - 7.6c\n4 an experiment was performed in which a crystalline substance was added to a beaker filled with a liquid at room temperature. the observations made during the experiment were as follows.\n1. the crystals dissolved\n2. a precipitate formed\n3. the bottom of the beaker felt warm to the touch\n4. bubbles formed in the water\nall of the observations are evidence that a chemical change occurred except-\na observation 1\nb observation 2\nc observation 3\nd observation 4

physical and chemical changes - 7.6c\n4 an experiment was performed in which a crystalline substance was added to a beaker filled with a liquid at room temperature. the observations made during the experiment were as follows.\n1. the crystals dissolved\n2. a precipitate formed\n3. the bottom of the beaker felt warm to the touch\n4. bubbles formed in the water\nall of the observations are evidence that a chemical change occurred except-\na observation 1\nb observation 2\nc observation 3\nd observation 4

Answer

Brief Explanations:

A chemical change results in the formation of new substances. Precipitate formation, heat - release (beaker feeling warm), and bubble formation usually indicate new substances are formed. Dissolving is a physical change where the substance just disperses in the solvent without forming a new substance.

Answer:

A. observation 1